Combustion system for internal-combustion engines and the like



Jam. 13; 1 25. 11,522,551

D. N. SHEPHERD COMBUSTION SYSTEM FOR INTERNAL COMBUSTION ENGINES AND THE} LIKE Filed April 9, 1925 .Patented .lan..1i'3 1925. I

UNITED STATES PATENT OFFICE;

DONALD 1v. SHEPHERD, or cmoneo, ILLmoIs.

I useful Improvements in Combustion tems for Internal-Combustion Engines and the like, of which the following is a specl- COMBUSTION SYSTEM FOR INTERNAL-COMBUSTION ENGINES AND THE LIKE.

To all whom it may concem:

Be it known that I, DONALD N. SHEPHERD, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new sand ficationi r This invention has to do with certain improvements in combustion systems for internal combustion engines. The invention has reference particularly to improvement-s in the construction of the engine at and adjacent to the spark plug, which improvements serve to materlally improve the action of the spark plug in firing the charge.

The main object of the invention is to provide an arrangement whereby oil or fuel of any kind in a liquid state is.-prevented from coming into direct contact with the spark plugs, and also in prevent carbonizing or fouling the plugs.

Another object of the invention is to provide an arrangement which will spread or flare the flame of i ited combustible gases from the spark p ug to the combustion chamber, thus providing a greatly improved igniting effect, enhancingof the flame into all portions of the combustion chamber, and reducing the tendency to-' wards detonation.

A. further object of the invention is to provide in conjunction with the spark plug and combustion chamber, a porous element such as a tube of ceramic or other material of sufficient dporosity to absorb liquid h drocarbons an oils, and being capable o retaining suflicient heat to distill oil the same into vaporous condition within the combustion chamber.

More particularly, it is an object of the present invention to provide an igniting chamber in conjunction with the combustion chamber, the spark plug acting directly within the igniting chamber and acting upon a relatively small quantity of gas contained therein. In this *connection, it is a further object to provide between the igniting and combustion chambers a Venturi tube or throat which will greatly restrict the flow of combustible gas into the igniting chamber on the compression stroke and enhance the pro agation of the flame from the igniting c amber into the combustion ch mber when h fir ng tak p this connection to the propagation Application filed April 9, 1923. Serial. No. 630,723.

In conjunction with the foregoing, it is a further object to so form this Venturi throat as to materially impede the tendency of liquid oil and fuel to pass into the igniting chamber, and so as to facilitate the outward flow from the igniting to the combustion chamber.

Further objects of the invention are to vaporize and volatilize the explosive mixture within the combustion chamber and thus to reduce carbon formation, cause carbon deposits to burnout, reduce crank case dilution, etc.

Other objects and uses of the invention will appear from a detailed description of the same, which consists in the ,features of construction and combinations of parts hereinafter described and claimed.

Referring to the drawing:

Figure 1 shows a vertical sectional view through the upper portion of the cylinder and valve mechanism of an internal combustion engine having applied thereto the features of the present invention;

- Fig. 2 is a full elevation of the device whereby an igniting chamber is established; Fig. 3 is a side view of the Venturi tube section independently; and

Fig. 4 shows a modified arrangement in which the Venturi tube section is incorporated directly into'the spark plug itself.

In the drawing the upper portion of the engine cylinder is designated by the numeral 5, and the piston by the numeral 15. usual above the-piston and within which the major portion of the work of the explosion and compression is performed.

The spark plug 17 is provided for firing the charge. This spark plug is provided with the usual electrodes 10 and 11, or may be formed in an other convenient manner. Ordinarily, the t plug threads directly into the threaded opening of the cylinder head, so that the electrodes act directly upon the charge within the combustion chamber 13.

According to one feature of the presen invention, I prefer to establish an igniting chamber 9 in immediate proximity to the electrodes'lO and 11, said igniting chamber 9 being also in communication with the combustion chamber 13, but ordinarily this communication is established in such a manner as to control the firing actiQ J. in a greatly improved manner.

readed stem 7 of the spark A combustion chamber 13 1s established passage .between of the cylinder. Th

For this purpose, I prefer to form the the igniting and combustlon chambers in such a manner as to establish in eifect a Venturi throat or between the chambers. This Venturi throat or passage is shown at 9 in Fig. 1 and at 9 in Fig. 4. e inner surface 14 ofthe Venturi throat is preferably roughened or corrugated towards the combustion chamber 13 so as to interfere with the movement of liquid oils or fuel from the combustion chamber into the igniting chamber. On the contrary, it is preferred that the othexnsurface 12 of the Venturi throat should be smooth and capable of passing the flame from the ignitingintothe combustion chamher with as little interference as possible.

he igniting chamber 9 may be established in any convenient manner; but the arrangement shownv in the drawing is a desirable arrangement. It includes a special fixture 6 which has at its upper end an proper size to receive the internal thread of spark plug itself, and at its lower end an exteriorly threaded neck 8 of thread directly into the spark plug opening is fixture 6 can, thereore, be seated into der opening and can spark plug itself in the shown in Fig. 1.

some cases it may use of a w the igniting cham passage. Such. porous either in the form of stone, zirconium or porous metal. porous material when used will serve to 'absorb any hquid oil or fuel which may be present .in the gas, thus considerably rcthen receive the manner clearly be desirable to make or in the Venturi porcelain, fire clay, Such ducmg the tendency towards carbon deposit; and afterwards this liquid oil or gas will spark plug 7 itself, and a establishing the Venturi same may be made by th this connection, of this latter material that it lscapable of absorbing substantialquantities of gas, partlcularly at high temperature, and it, theremanner of a passage, or the e use of mlca. In

fore, Wlll act porous material when used.

Owing 'to the shape of the Venturi passage, the same tends to flare or spread the flame flowing from the ignition to the combustion chamber thus materiall im roving ch the firing actioif. y p

applicatiomns to certain of thefeatures herein disclo is a continuation of my earlier filed application for Letters Patent of the United S explosive mixture within the combustion passage it will be desirable and point of the usual spark plug of porous material either in material may be it is. a peculiar characteristic b having a tates on lmprovements m means for ionizing and volatilizing the Serial No. 3

In those cases is used, the same w1ll have the effect of 597 ,982, which was filed v October pre-ignition', by allowing excess heat to escape readily, and by 'allowin cient cooling by each fresh 0 arge of gas entering the combustion chamber. This is because the porous nature of the material itself will allow a more ready dissipation of heat from its body, so that it cool quicker after each ignition.

In the modified arrangement shown in Fig. l, the' Venturi throat or passage is incorporated directly into itself. In the particular form illustrated in Fig. 4,-the electrodes 10 and 11 are placed somewhat beneath the. contracted portion of the Venturi throat, but in some cases p to place the electrodes sparking above the position of contraction of the Venturi throat, and I contemplate v struction and arrangement as within the scope and protection of my invention.

While I have herein shown and described only a single embodiment of the features of my present invention, still I do not limit 1n the claims.

I claim chamber of an Internal combustion engine having a spark plug port leading thereinto, of an ignition chamber fitting for said port, saidfitting including an ignition and aneck threaded to engage the threads of the spark plug port aforesaid, and also including an internally" threaded opening adapted to receive the shamber and chamber, said'Ventu'ri throat being made o'f porous material and having its wall which faces towards the combustion chamer roughened or corrugated to impede the backward flow of liquid oils and the like into the ignition chamber, and having itswall which faces the ignition chamber relatively smooth to avoid interference with the free flow of burning gases from the ignition chamber to the combustionchamber, substantially' as descrlbed. 2. The combination amber of an internal combustion engine spark plug of an ignition ch 0 uding an internally threaded ope equally this additional con- 1. The combination with the combustion the combustion the spark plug,

chamber 7 threads of the I Venturi throat with the combustion port leadln' g thereinto 7 her fittingfor said g adaptedto receive the threads of the spark plug itself, and a Venturi throat seated in the neck of said fitting between the ignition chamber and the combustion chamber, said Venturi throat being made of porous material, substantially as described.

3. The combination with the combustion chamber of an internal combustion englne having a spark plu port leading thereinto, of an ignition cham ber fitting for said port, said fitting including an ignition chamber and a neck threaded to engage the threads of the spark plug port aforesaid, and also including an internally threaded opening receive the threads of the spark plug itself, and a Venturi throat seated in the neck of said fitting between the ignition chamber and the combustion chamber, said Yenturi throat being made of material having the'property of absorbing liquid oils and the like, substantially.as described.

1. The combination \vth the combustion chamber of an internal combustion engine having a spark plug port leading thereinto, of an ignition chamber fitting for said port, said fitting including an ignition chamber and a neck threaded to engage the threads chamber and having of the spark plug aforesaid, and also including an internally threaded opening adapted to receive the threads of the spark plug itself, and including a passage within the neck aforesaid lying between the positions of the spark plug and the combustion chamber and having its inner surface which is exposed to the gases of combustion of ceramic material, substantiallyas described.

5. The combination with the combustion chamber of an internal combustion engine having a spark plug port leading thereinto, of an ignition chamber fitting for said port, said fitting including an ignition chamber and a neck threaded to engage the threads of the spark plug port aforesaid, and also including an internally threaded opening adapted to receive the threads of the spark plug itself, and including a passage within the neck aforesaid lying between the positions of the spark plug and the combustion its inner surface which is exposed to the gases of combustion of porous material, substantially as described.

DONALD n. snnrrmnn. 

